Last time I checked, cameos don't appear on the box art - which, you'll notice, that page doesn't mention - or act as the only character of the game, so no.
I'm sure that Mario's appearence on the Box Art was a marketing ploy by Nintendo to sell more units. Also if whoever wrote the page considers Mario's appearence in Alleyway as a cameo, IT IS A CAMEO, capice?
Besides, the word "cameo" means (according to dictionary.com)
a minor part played by a prominent performer in a single scene of a motion picture or a television play.
Mario, jumping into the paddle at the start, fulfils this definition (assuming you stretch the definition to include computer games).
